Lighting device for horticulture

Abstract

A grow light for providing light to one or more plants in a grow area, includes a first light source and a second light source. A first energy conversion component is disposed over the first light source and a second energy conversion component is disposed over the second light source. A power supply is configured to provide power to the first and the second light sources. A controller is configured to control the power supply to provide power to either the first light source or the second light source at a given time. The first energy conversion component converts light received from the first light source into a light having first spectrum and the second energy conversion component converts light received from the second light source into a light having second spectrum different from the first spectrum.

We claim: 
     
         1 . A grow light for providing light to one or more plants in a grow area, comprising:
 a light source;   a first energy conversion component disposed over a first portion of the light source and a second energy conversion component disposed over a second portion of the light source;   a power supply configured to provide power to the light source; and   a controller configured to control the power supply to control an intensity of the light source,   the first energy conversion component configured to convert light received from the first portion into a light having a first spectrum and the second energy conversion component configured to convert light received from the second portion into a light having a second spectrum different from the first spectrum.   
     
     
         2 . The grow light of  claim 1 , wherein the first spectrum has a peak intensity in blue wavelength range and the second spectrum has a peak intensity in red or yellow wavelength range. 
     
     
         3 . The grow light of  claim 1 , wherein the controller is configured to supply power to either the first or the second portions of the light source in response to one or more sensed parameters. 
     
     
         4 . The grow light of  claim 3 , wherein the one or more sensed parameters are selected from the group consisting of: time of day, season, plant surface temperature, surrounding air temperature, moisture/humidity level, plant type of the one or more plants, height of the one or more plants, chemical levels in the one or more plants, stage of growth of the one or more plants, carbon dioxide level, oxygen level, and light reflectance off of the one or more plants. 
     
     
         5 . The grow light of  claim 1 , wherein the first portion and the second portion of the light source have different emission characteristics. 
     
     
         6 . The grow light of  claim 1 , wherein the light source comprises blue light emitting diodes. 
     
     
         7 . The grow light of  claim 1 , wherein the first and the second energy conversion components are removably coupled to the grow light. 
     
     
         8 . The grow light of  claim 1 , wherein the first and second portions of the light source are disposed on different edges of a light guide panel such that the first and the second energy conversion components are respectively disposed between the first and second portions and corresponding edges of the light guide panel. 
     
     
         9 . A grow light for providing light to one or more plants in a grow area, comprising:
 a light source having a front face, the light source configured to emit light through the front face to illuminate the grow area;   an energy conversion component comprising a plurality of portions, the energy conversion component being positioned in one of the plurality of portions to the front face, wherein each of the plurality of portions of the energy conversion component converts light received from the light source into light having a different spectrum; and   a controller configured to position the energy conversion component to cause a respective portion among the plurality of portions of the energy conversion component to be exposed to the front face in response to one or more sensed parameters.   
     
     
         10 . A horticultural lighting system for providing light to one or more plants in a grow area comprising:
 a grow light including one or more light panels spaced away from the grow area, each of the one or more light panels including:
 a frame; 
 at least one light emitting diode coupled to an interior of an edge of the frame; 
 a light guide panel positioned in the frame, an edge of the light guide panel in communication with the at least one light emitting diode; and 
 at least one color conversion sheet coupled to a front surface of the light guide panel, 
   the grow light configured to output a uniformity of light outputted through the front surface of the light guide panel that is greater than 50%.   
     
     
         11 . The horticultural lighting system of  claim 10 , wherein the lighting system is configured to transition from a first configuration having the one or more light panels being spaced away from the grow area by a first distance, to a second configuration, having the one or more light panels being spaced away from the grow area by a second distance that is different than the first distance. 
     
     
         12 . The horticultural lighting system of  claim 11 , wherein the lighting system is configured to transition from the first configuration to the second configuration in response to one or more sensed parameters. 
     
     
         13 . The horticultural lighting system of  claim 12 , wherein the one or more sensed parameters are selected from the group consisting of: time of day, season, plant surface temperature, surrounding air temperature, moisture/humidity level, plant type of the one or more plants, height of the one or more plants, chemical levels in the one or more plants, stage of growth of the one or more plants, carbon dioxide level, oxygen level, and light reflectance off of the one or more plants. 
     
     
         14 . The horticultural lighting system of any one of  claims 10 - 13 , wherein the at least one light emitting diode emits blue light. 
     
     
         15 . The horticultural lighting system of any one of  claims 10 - 14 , wherein the at least one color conversion sheet is removable from the horticultural lighting system and replaceable by a different color conversion sheet. 
     
     
         16 . The horticultural lighting system of any one of  claims 10 - 15 , further comprising at least a second color conversion sheet coupled to a rear surface of the light guide panel. 
     
     
         17 . A method of cultivating one or more plants positioned in a grow area comprising:
 obtaining a grow light configured to provide light to the one or more plants, the grow light including one or more light panels spaced away from the grow area, each of the one or more light panels including:
 a frame; 
 at least one light emitting diode coupled to an interior of an edge of the frame; 
 a light guide panel positioned in the frame, an edge of the light guide panel in communication with the at least one light emitting diode; and 
 at least one energy conversion film coupled to a front surface of the light guide panel, 
   outputting, using the grow light, a light through the front surface of the light guide panel having uniformity which is greater than 50%.   
     
     
         18 . The method of  claim 17 , further comprising adjusting the distance that the grow light is spaced away from the grow area in response to one or more sensed parameters. 
     
     
         19 . The method of  claim 18 , wherein the one or more sensed parameters are selected from the group consisting of: time of day, season, plant surface temperature, surrounding air temperature, moisture/humidity level, plant type of the one or more plants, height of the one or more plants, chemical levels in the one or more plants, stage of growth of the one or more plants, carbon dioxide level, oxygen level, and light reflectance off of the one or more plants. 
     
     
         20 . The method of any one of  claims 17 - 19 , further comprising replacing the at least one energy conversion film with a different energy conversion film. 
     
     
         21 . A grow light for providing light to one or more plants in a grow area, comprising:
 a frame;   an opaque reflector positioned within the frame;   a light source disposed on the frame; and   a first energy conversion component disposed over a first portion of the light source and a second energy conversion component disposed over a second portion of the light source,   the first energy conversion component configured to convert light received from the first portion into a light having a first spectrum and the second energy conversion component converts light received from the second portion into a light having a second spectrum different from the first spectrum.   
     
     
         22 . A grow light control system for providing light to a plant in a grow area, comprising:
 a light source configured to emit source light to the plant in the grow area, the source light having a source light characteristic;   a light sensor configured to:
 detect reflected light from the plant, the reflected light having a reflection wavelength spectrum, and 
 generate reflected light sensor data representative of the reflected light having the reflection wavelength spectrum; 
   a controller configured to:
 receive the reflected light sensor data, and 
 determine any needed modification of the source light characteristic of the source light based on the reflected light sensor data and plant characteristic criteria. 
   
     
     
         23 . The grow light control system of  claim 22 , wherein the light sensor includes a photodiode. 
     
     
         24 . The grow light control system of  claim 22 , wherein the light sensor detects reflected light from the plant having a wavelength in a range from 660 nm to 760 nm. 
     
     
         25 . The grow light control system of  claim 22 , wherein the source light characteristic includes a source light intensity of the light source. 
     
     
         26 . The grow light control system of  claim 25 , further comprising:
 a power source configured to power the light source based on an amount of power transmitted to the light source,   wherein the controller is configured to alter the source light intensity of the light source by altering the amount of power transmitted by the power source to the light source.   
     
     
         27 . The grow light control system of  claim 22 , wherein the source light characteristic includes a light wavelength spectrum of the light source. 
     
     
         28 . The grow light control system of  claim 27 , further comprising:
 an energy conversion component disposed between the light source and the plant in the grow area, the energy conversion component configured to alter the light wavelength spectrum of the source light based on a characteristic of the energy conversion component, and   wherein the controller is configured to alter the light wavelength spectrum of the source light by altering the characteristic of the energy conversion component.   
     
     
         29 . The grow light control system of  claim 27 , wherein the plant characteristic criteria includes a criterion met when the plant transitions from a germination stage to a vegetative stage, and wherein the controller is configured to alter the light wavelength spectrum from being predominantly red wavelength range of 625 nm to 700 nm to having an increased amount of blue light in the 440 to 470 nm. 
     
     
         30 . The grow light control system of  claim 27 , wherein the plant characteristic criteria includes a criterion is met when the plant transitions from a vegetative stage to a reproductive stage, and wherein the controller is configured to alter the light wavelength spectrum from having a peak in red wavelength range of 625 nm to 700 nm to having an increased amount of light in the blue wavelength range of 440 nm to 470 nm. 
     
     
         31 . The grow light control system of  claim 22 , wherein the controller is configured to determine any needed modification of the source light characteristic of the source light based on the reflected light sensor data and plant characteristic criteria by the controller being configured to:
 determine whether the reflected light sensor data meets plant stage transition criteria;   in response to a determination that the reflected light sensor data meets plant stage transition criteria, modifying the source light characteristic of the source light; and   in response to a determination that the reflected light sensor data does not meet plant stage transition criteria, refrain from modifying the source light characteristic of the source light.   
     
     
         32 . A growth control sensor for a grow light system, the sensor comprising:
 an excitation light source configured to provide an excitation light pulse to a plant;   a photodetector configured to receive a light emitted from the plant in response to the excitation light received by the plant and generate an electrical signal based on the received light;   a filter circuit configured to process the electrical signal to remove components of the electrical signal generated by ambient light surrounding the plant to generate a data signal,   a communication circuit configured to transmit the data signal to enable data storage for further processing,   wherein the data signal is representative of a fluorescence output from leaves of the plant.   
     
     
         33 . The growth control sensor of  claim 32 , wherein the filter circuit is configured to:
 receive a first electrical signal generated by the ambient light prior to the excitation pulse being provided by the excitation light source,   receive a second electrical signal generated by the light in response to the excitation pulse, and   subtract the first electrical signal from the second electrical signal to generate a data signal.   
     
     
         34 . The growth control sensor of  claim 32 , wherein the photodetector is configured to detect fluorescence light from the plant having a wavelength in a range from 660 nm to 760 nm. 
     
     
         35 . The growth control sensor of  claim 32 , wherein the photodetector comprises an optical cutoff filter. 
     
     
         36 . The growth control sensor of  claim 32 , wherein the photodetector comprises a sensor selected from the group consisting of a photodiode, avalanche photodiode, a PIN diode, a charge-coupled device, a CMOS image sensor, a photomultiplier tube (PMT), and a combination thereof. 
     
     
         37 . The growth control sensor of  claim 32 , wherein the excitation light source is configured to emit the excitation pulse at an intensity such that the second electrical signal has a signal-to-noise ratio of greater than 1.5. 
     
     
         38 . The growth control sensor of  claim 32 , wherein the excitation light source is configured to emit the excitation pulse at an intensity in a range from 400 μmol/m 2 s to 800 μmol/m 2 s. 
     
     
         39 . The growth control sensor of  claim 32 , wherein the excitation light pulse has a wavelength in a range from 440 nm to 495 nm. 
     
     
         40 . A method of detecting the photosynthetic activity of a plant, the method comprising:
 generating, by a photodetector, a first electrical signal based on an ambient light detected by the photodetector;   turning on an excitation light source;   generating, by the photodetector, a second electrical signal based a fluorescence light detected by the photodetector; and   subtracting the first electrical signal from the second electrical signal to generate a fluorescence signal representative of a fluorescence output from leaves of the plant.   
     
     
         41 . The method of  claim 40 , wherein the excitation light source is configured to emit an excitation pulse at an intensity in a range from 400 μmol/m 2 s to 800 μmol/m 2 s. 
     
     
         42 . The method of  claim 40 , wherein the photodetector is configured to detect the fluorescence light from the plant having a wavelength in a range from 660 nm to 760 nm. 
     
     
         43 . The method of  claim 40 , wherein the fluorescence signal has a signal to noise ratio of greater than 1.5. 
     
     
         44 . A horticultural lighting system, comprising:
 the growth control sensor of  claim 32 ; and   a dimmable grow light configured to emit light to a plant in a grow area.   
     
     
         45 . The horticulture lighting system of  claim 44 , further comprising an energy conversion component disposed between the dimmable grow light and the plant in the grow area, the energy conversion component configured to alter the light wavelength spectrum of a light emitted by the dimmable grow light based on a characteristic of the energy conversion component, and
 a controller coupled to the growth control signal and configured to cause a change in light wavelength spectrum of the light emitted by the dimmable grow light by altering the characteristic of the energy conversion component.   
     
     
         46 . A horticultural lighting system comprising:
 the growth control sensor of  claim 32 ;   a grow light configured to emit light to a plant in a grow area; and   a control system configured to control one or more of temperature of air surrounding the plant, moisture/humidity level of an environment surrounding the plant, chemical levels in the plant, carbon dioxide level surrounding the plant, oxygen level surround the plant, and light intensity of the light emitted by the grow light.   
     
     
         47 . A growth control sensor, comprising:
 an excitation light source configured to provide light having a wavelength in a range from 400 nm to 500 nm to a plant; and   a photodetector configured to measure a light reflected and emitted from the plant in response to receiving a light from the excitation light source,   wherein the excitation light source has an intensity in a range from 400 μmol/m 2 s to 8000 μmol/m 2 s,   wherein the measured light reflected and emitted from the plant is indicative of a measure of photosynthesis rate of the plant.   
     
     
         48 . A method of remotely measuring plant photosynthesis rate, the method comprising:
 providing an excitation light having a wavelength in a range from 400 nm to 500 nm to the plant at an intensity in a range from 400 μmol/m 2 s to 8000 μmol/m 2 s; and   measuring a light reflected and emitted from the plant in response to the excitation light, wherein the measured light is indicative of the plant photosynthesis rate.   
     
     
         49 . A grow light for providing light to one or more plants in a grow area, comprising:
 a frame;   a light source disposed along an interior of an edge of the frame;   a light guide panel disposed in the frame, an edge of the light guide panel being in communication with the light source disposed on the interior of the corresponding edge of the frame, the light guide panel being configured to direct light received from the light source through a first surface of the light guide panel to a viewing hemisphere; and   a first energy conversion component disposed over a first portion of the light source and a second energy conversion component disposed over a second portion of the light source,   the first energy conversion component configured to convert light received from the first portion into a light having a first spectrum and the second energy conversion component configured to convert light received from the second portion into a light having a second spectrum different from the first spectrum.